Fabricated wood staging plank



Dec; 23, 1947. P. B. ATTWELL FABRICATED WOOD STAGING PLANK Filed Aug'. 29', 1945 W R./ N e R m a 5 B W Patented Dec. 23, 1947 UNITED STATES PAT ENT OFFIQE.

FABRICATED WOOD PLANE P Bob Attwell, Sea-titles Walsh. Application August 29, 194-5, sen-amt: 613.2 77

1- Claim;

This invention relates to a built up or fabrioated wood staging plank of the type commonly used connection with various kinds of scaffolds by workmen such' as painter-s carpenter's and the like.

An object of this invention is to provide a fabricated wood staging plank that is much lighter in weight. and. at. th same time much stronger than the usual wood staging plank of the same over all cross sectional size and length.

Another object is to provide a: fabricated wood staging plank that isnet expensive to construct, that is efficient and durable in use and that is waterproof.

Boards, such as two by twelve inch wooden planks of any desired length, are ordinarily used as staging planks on scaffolds to support workmen such as painters, carpenters and the like. These planks are ordinarily twelve to sixteen feet long and are heavy for the workmen to handle. Also these long heavy planks add considerable to the weight on the scaffold and the margin of safety of the longer wooden planks, when they are supported from points near their ends, is not as high as it should be.

A sixteen foot fabricated wood staging plank made in accordance with this invention is about one-third the weight of an ordinary clear fir staging plank of the same length, width and thickness and will withstand about three times as great a load when it is supported from its two ends and the load is applied midway of its length.

It is therefore an object of this invention to provide a staging plank that is safer for the workmen to use than is the ordinary staging plank.

Other objects of this invention will be apparent from the following description taken in connection with the accompanying drawings.

In the drawings Figure l is a plan view of a staging plank constructed in accordance with this invention.

Fig. 2 is a longitudinal section of the same taken on broken line 2--2 of Fig. 1.

Fig. 3 is a longitudinal section taken on broken line 3-3 of Fig. 2.

Fig. 4 is a cross section on a larger scale than the other figures taken on broken line 4-4- of Fig. 3.

Like reference numerals designate like parts throughout the several views.

This staging plank comprises three longitudinally extending parallel frame members Ill, II and I2; two transverse end headers I3 and I4 and two sheets of plywood I5 and I6 which form thetwan'at sides or tire-plank: The longitudinal frame members In and II are positioned atithe sides of the plank and the frame member I2 substantially medially thereof. Preferably the longitudinalx frame: members W,- I I and I2 and the: transverse endheaders I3 and 14' are pieces of relatively light weight" strong wood, such as spruce; about th ree uarters of an inch thick and about one and: three quarters inches wide The sheets I 5 and lit which form the faces-of the plank may" be threeply fir? ply-wood one quarter of an inch thick with the grain of. the two outside plies of each sheet running lengthwise of the sheet.

The strength of this staging plank can be increased about thirty percent by securely gluing to the inner face of each side frame member Ill and II, medially between its two ends a one-half by one and three fourths inch spruce wood reinforcing strip I 1. Each reinforcing strip I1 is preferably about one third of the length of the plank. The reinforcing strips I! add some weight to the plank and for this reason preferably are omitted from planks not intended for heavy service.

Preferably short cleats I8 are securely glued to opposite sides of the medial frame member I2 near the two ends thereof. These cleats cooperate with the frame member I2 to provide solid wood of sufficient width so that a transverse hole I9 at least three quarters of an inch diameter may be bored through the plank adjacent each end thereof medially of its width.

Preferably the end portions of the medial frame member I2 are transversely bowed slightly as shown in Figs. 1 and 3 to displace the cleat carrying ends of said frame member I2 far enough from the medial axis of the plank so that when the holes I9 are bored midway between the two sides of the plank they will be bored partly in the cleats I8 and. partly in the member I2 and there will be no danger of the holes I9 cutting through the sides of the member I2 and leaving openings through which water could enter.

In assembling this plank preferably waterproof glue is used and all of the parts are securely glued together under pressure in such a manner as to provide a hollow plank that will exclude water, that is light in weight, and that is very strong. Preferably the wood from which these planks are made is treated to render it highly resistant to moisture, weather conditions and fungus.

The holes I9 facilitate handling the planks and may receive pins or bolts which help to prevent displacement of the planks on their supports, or these holes may receive cables or flexible fastening members by which the planks may be secured to their supports. These planks are light enough so that a workman standing on one of said planks can, with his foot, readily move another of said planks along the scaffold means on which it is supported to a new position. This saves time and labor. stronger than ordinary wooden staging planks of the same size, are safer to use.

These planks are substantially the same thickness as ordinary staging planks and can be used on all types of scaffolds, swinging or otherwise, where ordinary staging planks are used. 7

The medial rib l2 provides support to the plywood sheets 15 and I6 midway between the two sides of the plank and makes it possible to use plywood sheets of one quarter inch thickness.

Obviously changes in this staging plank may be made within the scope of the following claim.

I claim:

A fabricated wood staging plank of light weight and great strength comprising a relatively long narrow thin frame formed of two parallel side frame members, a medial fram member and two head pieces all adhesively secured together; two short cleats adhesively secured to opposite sides of said medial frame member near the respective ends thereof providing increased thickness at the location of said cleats; and two thin plywood sheets adhesively secured to opposite Also these planks, being sides of said frame, said plywood sheets serving as a tension and a compression member on the top and bottom sides of said frame respectively when the plank is positioned on spaced apart supports and subjected to a load; said plank having a hole therein adjacent each end mid way between the two sides of the plank, each hole extending through the two plywood sheets and through the medial frame member and cleat therebetween.

P BOB ATTWELL.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,801,904 Davidson Apr. 21, 1931 2,073,896 Loets-cher Mar. 16, 1937 2,089,865 Voss Aug. 10, 1937 2,199,938 Kloote May 7, 1930 2,335,046 Droeger Nov. 23, 1943 2,236,948 Maurer Apr. 1, 1941 2,243,022 Thomas May 20, 1941 2,261,831 Farr et a1. Nov. 4, 1941 2,274,703 John Mar. 3, 1942 FOREIGN PATENTS Number Country Date 338,051 Great Britain Nov. 13, 1930 769,716 France June 11, 1934 

